In the last 30 minutes of cooking, baste the ribs with the teriyaki sauce. When they are done, the pork will pull away from the bone and you will see about 1/2-inch of bone showing. Just before you're ready to eat, baste the ribs with the teriyaki sauce again and stick them under the broiler for 5 to 8 minutes to make the spareribs a nice crusty brown. (Keep a close eye on these guys - ribs go from perfectly crisp to perfectly burnt seconds.) Separate the ribs with a cleaver or sharp knife, pile them on a platter, and pour on the remaining sauce. Sprinkle with sesame seeds, chopped cilantro, and green onion before serving.